wastegate dump tube, into atmosphere or ....

[statickx991]

hey i have a fully build s14 sr in my s13 chassis, and i have the peakboost top mount with a gt3071r and i was wondering, when i make the downpipe should i run the wastegate dump tube back into the exhaust or say fck it and into the atmosphere. and why.

[Bronze MFP]

Here's my personal experience with running an open dump tube.It's loud. REALLY loud. and it will be loud any time you get close to the boost level the spring is for because the wastegate starts to crack open before then. I thought it wouldnt be a problem, i could keep quiet in traffic... nope. anytime I was even partially on throttle and boost got up, so did the noise.it was fun in the beginning, but after 6 months or so, the novelty wore off and it got kinda embarassing.People will argue that it's better for boost control, and it is, but if you run your dump tube into the exhaust somewhere in the middle section of the downpipe or farther back, it should be fine. With it plumbed back into the exhaust, you wont attract the attention of the cops everywhere and you'll be able to hear the sweet sound of your turbo a lot better. In the end, its your car, do what you like, but i don't think i'd ever run an open wastegate again unless it was the only way to stop boost creep.

[CMG]

Are you talking about an sr or a mazda rotary? From what I've read on Nico it's better for the sr to recycle than be open to atmo. You can run it open, but there's some reason not to (dunno what that reason is).

[statickx991]

Here's my personal experience with running an open dump tube.It's loud. REALLY loud. and it will be loud any time you get close to the boost level the spring is for because the wastegate starts to crack open before then. I thought it wouldnt be a problem, i could keep quiet in traffic... nope. anytime I was even partially on throttle and boost got up, so did the noise.it was fun in the beginning, but after 6 months or so, the novelty wore off and it got kinda embarassing.People will argue that it's better for boost control, and it is, but if you run your dump tube into the exhaust somewhere in the middle section of the downpipe or farther back, it should be fine. With it plumbed back into the exhaust, you wont attract the attention of the cops everywhere and you'll be able to hear the sweet sound of your turbo a lot better. In the end, its your car, do what you like, but i don't think i'd ever run an open wastegate again unless it was the only way to stop boost creep.

thats true, i think im goign to make a dumptube to go into the middle of the downpipe.

[statickx991]

Are you talking about an sr or a mazda rotary? From what I've read on Nico it's better for the sr to recycle than be open to atmo. You can run it open, but there's some reason not to (dunno what that reason is).

And i think what your talking about is the BOV and it is better to recycle IF your using a MAF sensor like the sr's have cuase it can make it pretty rich at that point where it is programed for that extra air, but mine i got a apexi power fc djetro so it converted it to map sensor so i dont have to recycle. plus i think it makes it easier to tune and more power

[CMG]

Yeah, I was totally off, my bad.

[4cefed]

Well, In theory, you would see more HP if you dumped to atmosphere rather than to rejoin the exhaust. I Don't think the noise would be so bad if you used some kind of "fast boost" set-up like that Dawes devices controller. Then the wastegate wouldn't open at all until you were near peak boost. I think it sounds great, but I live in the boonies.

[compression]

I recirc my wastegates. The sound gets annoying after a while. There is no real difference in performance or boost control (assuming everything is done correctly in the first place).Vibrant had a cool little wastegate muffler at SEMA this year, but I dont see it on their website. You can put it on your wastegate outlet and it muffles the sound when the gate opens. This is cool because you eliminate the annoying sound, and you dont have to deal with the headache of plumbing it back in, which can be a pain sometimes to do cleanly.In the end, its a matter of opinion. You will not notice any difference in performance.

[Bronze MFP]

you can use a lawn mower muffler on an open wastegate dump pipe to quiet it down too. only thing with that is the muffler wears out too quickly and starts to rattle and sound like a honda exhaust. for high HP setups, and open dump helps, but we're talking 350+hp on up.and still, for a street driven car, you'll eventually want it recirculated anyways, so just do it from the get go and save yourself the trouble later on.

[HighRev'nJAWN]

Hey everyone Im new to this forum and would first off like to say hi to everyone. As for running the wastgate dump tube back into the exhaust stream, if you do this you will actually lose power. Because when you release the hot exhaust directly from the turbo through the wastegate and dump pipe, you want to instantly release this heat to the atmosphere. By running this tube into the exhaust downpipe, it will restrict the heat from exiting the pipe due to the exhaust coming from the engine initually trying to force the gasses from the the dump pipe back into the wastegate. A buddy of mine actually tested this theory on his 05 SRT4 and after welding the dump tube to the downpipe, he dyno tested and actually lost 38WHp. So what he did was run a pipe along the downpipe and welded a seperate magnaflow muffler 2.25" in diameter to the tube and eliminated the noise while gaining back the lost Hp.